#define _CRT_SECURE_NO_WARNINGS 1
#include <stdio.h>
#include <stdlib.h>

void WriteLetter(FILE* f, int n);

int main()
{
    FILE* f = fopen("Letter.txt", "w");
    int n;
    if (f == NULL)
    {
        perror("fopen");
        return 1;
    }
    scanf("%d", &n);
    WriteLetter(f, n);
    fclose(f);
    f = NULL;
    return 0;
}

void WriteLetter(FILE* f, int n)
{
    char arr[26];
    int i = 0;
    for (i = 0; i < 26; i++)
    {
        arr[i] = 'A' + i;
    }
    for (i = 0; i < n; i++)
    {
        fputc(arr[i], f);
    }
}

